Time stamp



Nov. 22, 1938. A. c. JOHNSON r-:T AL.

TIME STAMP Filed May 20, 1936 2 Sheets-Sheet 1 Nov. 22, 1938.'

A. C. JOHNSON ET AL TIME STAMP Filed May 20, 1936 2 Sheets-Sheet 2 NIT QN a k.,

N) ww I M fw hw/ 1m PW" E ww WN m NW w\\%\ WW f c N W Patented Nov. 22, 1938 UNITED STATES TIME STABU Austin G.' Johnson and Theodore M. Wroble, Chicago, Ill.

Application May 20,

3 Claims.

Our invention relates to time stamps adapted for imprinting the year, month, day, hour and minute upon documents and the like. Stamps of the kind described usually provide a rubber pad having fixed elements forming a dial, rotating elements providing hour and minute pointers and a dater device providing elements adapted to be shifted to indicate the year, month and day of the month. As heretofore constructed, the elements carried by the dater device tend to yield less under pressure than the hour and minute elements whereby the latter take less ink from a pad and have less contact with a document or surface to be stamped. The dater impressions as a result are frequently clearer and more distinct than the impressions made by the pointers and dial or time elements. It is one of the objects of the invention to provide improvements in time stamps whereby impressions of equal weight and distinctness are transferred by both the time and dater elements to the documents to be impressed therewith.

rThe impression elements of dater devices as ordinarily constructed and as mounted on bands have a tendency to creep or crawl by reason of the movement of the bands resulting from irregular pressure to which the elements are subjected. The impressions formed by the dater elements are thereby formed in irregular instead of straight lines with the edges of the impressions more or less illegible, and it is another object of the invention to provide an improved mounting for dater devices whereby the dater elements are locked against relative movement while being impressed upon an ink pad or a surface to which impressions are to be transferred.

In applying a stamp to an ink pad or to a document for transferring an impression thereto, the stamp is frequently inadvertently slightly twisted especially at the instant of maximum pressure. If the twisting movement of the stamp is in a direction opposite to the travel of the rotatable pointers, slack or backlash of certain gears and pinions actuating the pointers will result on account of the pointers remaining stationary on the ink pad or on the surface with which they are in Contact. The resulting movement of the dial relative to the pointer elements produces an inaccurate time reading since the pointers are in advance of their correct position. This is particularly true of the minute pointer by reason of the larger number of gears and pinions operable to rotate it and since in general the backlash is proportional to their number. In ordinary clock mechanism, the acceleration of the 1936, Serial No. 80,780

minute pointer due to such twisting is frequently such that its reading is as much as two minutes in advance of the correct reading. If the stamp is applied successively to documents during the period immediately following the inadvertent A., twisting movement and before the gears and pinions have had time to take up the slack, the impressions indicating the time will be in error.

If during such successive applications of the stamp to documents there should be an inad- 5u vertenttwisting movement of the stamp in a direction tending to correct the position of the pointers, the later impressions will show an earlier time than do the impressions actually earlier transferred to the documents while the pointers 15 were accelerated. It is another object of the invention to provide improvements in time stamps operable to minimize slack or backlash in the gear trains actuating the pointers due to inadvertent manipulation of the stamp while being pressed against an ink pad or document to be stamped and thereby preventing successive time impressions from being recorded other than in the actual order in which they are successively impressed.

Still another object of the invention is the provision of an improved mounting for dater devices whereby they yield under pressure in an amount such that the impression faces of the dater elements remain in a common plane with the corresponding faces of the time elements under all conditions of pressure to which the stamp may be subjected with the result that the elements are uniformly inked and impressions of equal distinctness are transferred to the surfaces of documents to which the stamp is applied.

Many other objects and advantages of the construction herein shown and described will be obvious to those skilled in the art from the disclosure herein given.

To this end our invention consists in the novel construction, arrangement and combination of parts herein shown and described and more particularly pointed out in the claims. 45

In the drawings, wherein like reference characters indicate like or corresponding parts:

Fig. 1 is an elevational view of a time stamp embodying the principles of the invention and showing the stamp in slightly elevated spaced relation to a member providing a support therefor;

Fig. 2 is a sectional view along the line 2 2 of Fig. J3;

Fig. 3 .is a vertical sectional View taken approximately along the center and transversely to the clock face of the stamp;

Fig. 4 is a view of a fragmentary portion of the stamp including the dater device;

Fig. 5 is a plan view of a portion of the base or impression forming end of the stamp;

Fig. 6 is a view along the line 6 6 of Fig. 3; and

Fig. '1 is a View along the line 1--1 of Fig. 2.

Referring now more particularly to the drawings, the numerals I and II, respectively, generally designate a time stamp and a base member forming a support for the stamp. The stamp I0 includes a casing I2, a handle I3, and a plate I4 providing a bottom wall for the casing. The side walls of the casing project downwardly beyond the plate I4 to form therewith a receptacle in which a cushion pad I is mounted and is fastened to the plate by a layer of adhesive material, not shown, or in any other suitable manner.

The pad I5 provides a plurality of elements I6 so arranged as to transfer an impression of a dial to the surface to be printed or stamped. A shaft I1, rotatably mounted on a bracket I8, is operatively connected with the usual clock mechanism including a horological motor shown as mounted in the casing I2 but not described inasmuch as the mechanism and motor constitute no part of the invention. The shaft I1 is concentric with the dial elements I6 and has a cylinder I9 fixedly mounted on its lower end. The cylinder I9 provides a mounting for a cushion pad 20, the latter having a projecting portion forming a minute pointer 2I. The shaft I1 is driven by the clock mechanism at such a rate that it makes one coniplete revolution every hour. A pinion 22, xedly mounted on the shaft I1, forms one element of a gear train actuating a sleeve 23 rotatably mounted on the shaft I1. The pinion 22 meshes with a gear 21 mounted on and rotatable about a stud shaft 26. The hub of the gear 21 provides a pinion 28 in mesh with a gear 25 provided by the top flange of the sleeve 23, the diameters of the gears and pinions respectively being such that the sleeve makes one complete revolution every twelve hours.

The lower end of the sleeve 23 provides a mounting for an hour pointer 24. The pointers 2I and 24 and the dial elements IE all have their impression faces in a common plane perpendicular to the axis of rotation of the shaft I1. The combined depth of the pad I5 and of the characters I5 is substantially the same as that of the pad 20 and pointer 2|. The depth of the pointer 24 is approximately equal to the combined depth of the pad 2l! and pointer 2I and is of the same material. Since the material yields equally under equal pressures, the impression faces of the time elements are always in a common plane regardless of variations in the amount of pressure applied thereto.

A dater device carried by the casing I2 is mounted in a U-shaped frame 32. The plate I4 and the cushion I5 are respectively recessed and apertured to receive the lower end of the dater device. Lugs 33 on the opposite sides of the frame 32 form stops limiting the amount the dater device may project through the impression face of the stamp. The upper transversely extending end portion of the frame 32 is positioned in a recess 34 provided by the adjacent portion of the casing I2 and by a removable plate 39. A spring plate 35, positioned in the recess 34, tends to hold the frame 32 with the lugs 33 seated on the plate I4 as shown and yields to permit upward movement of the dater device under pressure.

The dater device is of the usual construction and comprises a plurality of thin endless flexible bands 36 respectively carrying a plurality of elements generally designated by the numeral 30 to indicate the year, month, day of the month and a. m. and p. m. indicia, the bands being adapted to be manipulated in the usual manner by serrated discs 31 projecting through slots 38 in the plate 39. The bands 36 extend around an upper roller 44 on which the discs 31 are rotatably mounted and also around a lower curved end portion (not shown). The discs 31 are respectively operatively connected with the bands 36 to actuate the latter and successively bring the individual band elements 30 into operative position with their impression faces in a common plane substantially coinciding with the common plane of the impression faces of the time elements. When the stamp is pressed down on an ink pad or document for stamping, the dial elements I6 and the pointers 2I and 24 are retracted considerably due to their resiliency and conformation and also to the resiliency of the cushion pads from which they project. Since the dater elements 30 are mounted on the flexible bands 36 and the latter have an unyielding bearing on the lower end of the frame which provides no cushioning effect, the pressure on the dater elements is sufficient to retract the dater device by the yielding of the spring plate 35. The impression faces of all operatively positioned elements are thereby maintained in a common plane, and, as a result, the dater and time elements are equally inked and their respective impressions are uniformly transferred to a document when the stamp is applied thereto.

The tendency of the operatively positioned dater elements to creep about the lower end of the dater device and to be irregularly aligned is prevented by locking the discs 31 against movement when pressure is applied to the stamp. For this purpose we have provided a downwardly projecting member 40 having a sharp wedge-shaped straight edge which enters the adjacent serrations of the discs 31 as they are moved upwardly with the dater device and locks the discs against relative movement. Since the dater bands are movable only by and with the discs 31, the operatively positioned da-ter elements are held in accurate alignment by the locked discs when the applied pressure is at a maximum and such incipient creeping as may have already occurred is corrected by the engagement of the member 40 with the discs.

The retraction of the dater device resulting in locking of the dater elements 30 as described is also utilized to lock the shaft 26, pinion 21, and gear 28 against rotation and thereby minimizes back movement and prevents acceleration of the pointers 2I and 24 which otherwise may result from manipulation of the stamp. For this purpose, the unitary member, comprising the flange gear 21 and the hub pinion 28, also provides a brake drum 29 rotatable therewith. An arm 4I, oscillatable about a pivot 42, has one end engaging the bevelled face of the adjacent lug 33 and the other end operatively related to the 'drum 29. Upward movement of the dater device brings the bevelled edge of the lug 33 into contact with the adjacent end of the arm 4I. The lug 33 acts as a cam rotating the arm 4I to bring it into braking contact with the drum 29. The gears 25 and 21 and the pinion 28 are thereby prevented from rotating during the instant of maximum pressure on the stamp. This effectively prevents any acceleration of the pointers tending to inaccurate reading by reason of inadvertent twisting movement of the stamp and also limits back movement of the pointers 2l and 24 to the clearance between the pinion 25 and gear 28 and between the pinion 22 and gear 21 respectively,

Thus it will be seen that we have provided improvements in time stamps Which tend to maintain the impression faces oi a plurality of time and operatively positioned dater elements in a common plane under all degrees of pressure, which locks the dater elements against relative transverse movement under pressure, and also prevents movement of certain of the gears and pinions, actuating the pointers, when the pointers are impressed upon an ink pad or a document to be impressed therewith.

Having thus described our invention, it is obvious that various immaterial modifications may be made in the same without departing from the spirit of our invention, hence we do not Wish to be understood as limiting ourselves to the exact form, construction, arrangement and combination of parts herein shown and described or uses mentioned.

What we claim as new and desire to secure by Letters Patent is:

1. The combination with a time stamp comprising a horological motor, and a casing providing an impression face, of a resilient element and a retractible dater device projecting from said face, said element being adapted to produce an impression on a selected surface and said device being adapted to be retracted by exerting pressure on the casing in the direction of said face, means actuated by said motor for rotating said element, and a member operatively related to said element actuating means and device, said member being operable by retraction of said device to engage Said means and thereby to temporarily prevent rotation of said element while the device is retracted.

2. The combination with a time stamp comprising a horological motor, a casing providing an impression face, a resilient element rotatable about and a retractible device projecting through said impression face, and means actuated by the motor for rotating said resilient element, of yieldable means tending to maintain the device in said projected position, said device including a frame, a substantially non-resilient impression element carried by the frame, said rotatable element being adapted to be compressed and said device to be correspondingly retracted by pressure exerted upon the stamp with said resilient and nonresilient elements in contact with a surface to be impressed, and a movable member operatively related to said device and to said resilient element actuating means, said member being operable by retraction of the device to engage said actuating means and thereby to temporarily prevent rotation oi the resilient element.

3. The combination with a time stamp comprising a horological motor, a casing providing an impression face, a resilient impression element rotatable about and a retractible device projecting through said impression face, and means actuated by the motor for rotating said resilient element, of yieldable means tending to maintain the device in said projecting position, said device including a frame, a plurality of connected substantially non-resilient impression elements carried by the frame, means operable to selectively position said connected elements on the projecting end of the frame with their impression faces in the same plane as the impression face of the rotatable element, and means operating as a latch to prevent movement of said elements relative to the frame when the device is retracted, said rotatable element being adapted to be compressed and said device to be correspondingly retracted by pressure exerted upon the stamp with said resilient and frame elements in contact with a surface to be impressed, and a movable member operatively related to said device and to said resilient element actuating means, said member being operable by retraction of the device to engage said motor actuated means and thereby to temporarily prevent rotation of the resilient element.

AUSTIN C. JOHNSON. THEODORE M. WROBLE. 

